No, ShortPixel Image Optimizer only optimizes the images on your site, it doesn’t change the URLs.
What it can do, though, is to change the markup of your page source code, but only if you choose the “Using the <PICTURE> tag syntax” option (located on Settings > ShortPixel > WebP/AVIF & CDN). That option makes the plugin offer additional URLs for the WebP images so that they can be used by WebP-aware browsers, but that doesn’t mean the URLs of your current images will be changed.
